L-734,217 is a novel, oral antagonist of the platelet glycoprotein IIb/IIIa, or fibrinogen receptor. This double-blind, placebo-controlled, single oral dose study will investigate the safety, tolerability, pharmacokinetics and pharmacodynamics of L-734,217 in healthy elderly subjects. Inhibition of platelet function will be assessed by conventional platelet aggregation, platelet agglutination (RPFA, Accumetrics) and platelet-dependent hemostasis (PFA-100, Dade Behring).